Methyl pyrrolidinone chitosan, production process and uses thereof
CA 2074517 A1 · Owner: Merck Patent Gesellschaft Mit Beschraenkter Haftung · Inventors: Muzzarelli, Ricardo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Modified chitins and chitosans with recurring units of formula (I), wherein R denotes -NH2, -NHCOCH3 and R' with R' being, present in at least 30 % of the recurring units characterized in, that R' represents a group of formula (II) in a proportion of at least 90 %. Due to their favourable biological properties these, materials are advantageously useful in medical and cosmetical applications.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed November 18, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 18, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 18, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.